電位器接線片多工位級進模及自動送料裝置的設計(全套含CAD圖紙)
下載后文件包含有 CAD圖紙和說明書,咨詢 Q 197216396 或 11970985 畢業(yè)設計(論文)說明書題 目:電位器接線片多工位級進模及自動送料裝置的設計學院: 機電工程學院 專 業(yè):機械設計制造及其自動化學生姓名:學 號:指導教師單位:姓 名:職 稱:題 目 類 型 : 理 論 研 究 實 驗 研 究 工 程 設 計 工 程 技 術 研 究 軟 件 開 發(fā)下載后文件包含有 CAD 圖紙和說明書,咨詢 Q 197216396 或 11970985摘 要電位器在日常生活中的應用非常之廣泛,尤其是在電子設備上。它是一種可調(diào)的電子元件,由一個電阻體和一個轉動或滑動系統(tǒng)組成,主要起分壓和分流作用,其工作原理跟可變電阻器比較相近,而且種類也比較的多。近來多工位級進模在模具沖壓中越來越重要,本次模具畢業(yè)設計研究的是電位器接線片的沖壓工藝與模具設計,主要通過運用多工位級進模來完成,將有效提高沖壓件質(zhì)量與生產(chǎn)效率。在本次設計中繪制了產(chǎn)品零件圖并分析了電位器接線片的成型工藝特點,其中包括利用對工件展開圖的尺寸計算、工件的工藝分析、沖裁力與拉深力的計算、模具設計中的難點,如接線片的彎曲和修邊,確定了級進模的排樣方案和模具總體結構及自動送料裝置。該級進模有沖裁、拉深、整形、脹形等 7 個工位。詳細介紹了凸模、凹模、固定板、卸料裝置等零部件的設計和制造,壓力機的選用以及相關的輔助裝置。同時闡述了模具的工作過程、各成形動作的協(xié)調(diào)性、以及凸模和凹模鑲塊的裝配間隙,并制定典型零件的加工工藝。關鍵詞:電位器;接線片;多工位級進模;壓力機;自動送料下載后文件包含有 CAD 圖紙和說明書,咨詢 Q 197216396 或 11970985AbstractPotentiometer applications in daily life is very extensive, especially in electronic devices. It is an adjustable electronic components, by a resistor body and a rotating or sliding system components, main and diverted from the partial pressure, it works with the variable resistors are quite close, but also more multi-species. Recently, multi-position progressive die stamping more and more important in the mold, this mold is the design of graduate potentiometer lug stamping process and die design, primarily through the use of multi-position progressive die to complete, will effectively improve the stamping pieces of quality and production efficiency. In this design drawing parts in the graph and analyze the potential wiring film forming process features, including the use of the size of the workpiece calculated expansion plan, part of the process analysis, the blanking force and drawing force calculation, mold design of the difficulties, such as lugs bending and trimming, set the layout for progressive die and mold the overall program structure and automatic feeding device. The progressive die with blanking, drawing, shaping, expansion, etc. 7 station. Details of the punch and die, fixed plate, unloading equipment and other parts of the design and manufacture of presses and related auxiliary equipment used. It illustrates the working process of the mold, the forming coordination of movements, as well as punch and die inserts assembly space, and to develop typical machining process. Key words : potentiometers;lug;multi-postion progressive die;press;automatic feeding下載后文件包含有 CAD 圖紙和說明書,咨詢 Q 197216396 或 11970985目 錄第一章 緒 論 .1第二章 零件圖分析和計算 .12.1 工藝分析.12.2 工藝計算.22.2.1 加工零件的彎曲 .22.2.2 彎曲件的毛坯長度計算 .22.2.3 彎曲高度要求 .3第三章 工藝方案與模具形式 .33.1 零件的基本工序.33.2 模具方案的設計.3第四章 工序及排樣圖設計 .44.1 加工工序.44.2 排樣設計計算.5第五章 壓力、壓力中心計算 .55.1 沖裁力.55.2 彎曲力.65.3 總壓力.65.4 壓力中心.65.5 沖裁間隙.85.5.1 沖裁間隙對沖件質(zhì)量的影響 .85.5.2 對模具壽命的影響 .85.5.3 對沖裁力及卸料力的影響 .9下載后文件包含有 CAD 圖紙和說明書,咨詢 Q 197216396 或 119709855.5.4 合理間隙選用 .105.6 模具刃口尺寸計算.105.6.1 凸、凹模刃口尺寸計算原則 .115.6.2 凸、凹模尺寸計算 .11第六章 級進模具設計 .126.1 模具總結構設計.126.2 凸模的結構設計.136.3 凹模的結構設計.136.4 導料系統(tǒng).156.5 頂出裝置.156.5.1 頂出裝置的類型 .156.5.2 常用類型 .166.6 監(jiān)控裝置.176.6.1 監(jiān)控裝置的作用 .176.6.2 監(jiān)控裝置的工作原理 .176.7 固定板.186.8 墊板.196.9 螺釘和銷釘.196.10 級進模的模架.206.10.1 級進模模架的精度選擇 .206.10.2 選用模架的依據(jù)和考慮的問題 .216.11 導柱、導套的基本結構與安裝方式.22第七章 級進模壓力機的選用 .237.1 壓力機類型的選擇.237.1.1 壓力機類型 .237.1.2 壓力機規(guī)格 .247.2 壓力機的技術參數(shù).247.2.1 公稱壓力的選擇 .247.2.2 行程次數(shù) .25下載后文件包含有 CAD 圖紙和說明書,咨詢 Q 197216396 或 119709857.2.3 滑塊行程 .257.2.4 閉合高度 .257.2.5 工作臺面尺寸 .26第八章 輔助裝置 .268.1 自動送料裝置.268.1.1 自動送料裝置分類 .268.1.2 輥軸自動送料裝置 .268.1.3 單邊輥軸自動送料裝置的工作過程 .268.1.4 單邊輥軸自動送料裝置的結構特性 .288.1.5 輥軸送料的特點及應用場合 .348.1.6 軸的設計及校核 .348.1.7 軸承的設計和校核 .378.1.8 鍵的設計和校核 .398.2 卸料裝置.408.2.1 卸料裝置的設計 .408.3 選擇沖壓設備.43結論 .44致謝 .45參考文獻 .46附錄 .47下載后文件包含有 CAD 圖紙和說明書,咨詢 Q 197216396 或 11970985下載后文件包含有 CAD 圖紙和說明書,咨詢 Q 197216396 或 119709851第一章 緒 論模具在我們?nèi)粘I钪械膽梅浅V畯V,所用器具幾乎均需用模具來成型實現(xiàn),例如在電子、汽車、電機、電器、儀器、儀表、家電和通信等產(chǎn)品中,其中 60%80%的零部件都要依靠模具成形。用模具生產(chǎn)制件所具備的高精度、高復雜程度、高一致性、高生產(chǎn)率和低消耗,是其他加工制造方法所不能比擬的。模具又被稱為“效益放大器”,用模具生產(chǎn)的最終產(chǎn)品的價值往往是模具自身價值的幾十倍甚至是上百倍。沖壓模具如今在生產(chǎn)中的地位越來越重要,而標志沖模技術先進水平的多工位級進模,是我國重點發(fā)展的精密模具品種。級進模能夠在一副模具內(nèi)完成復雜零件的沖裁,彎曲,拉深,立體成型以及裝配等復雜工藝,具有生產(chǎn)效率高,操作安全可靠,可以加工復雜零件等特點而推崇備至。有代表性的是集機電一體化的鐵芯精密自動疊片多功能模具,已達到國際水平。其他如 48、54、68 條腿集成電路柜架多工位級進模、電子槍硬質(zhì)合金多工位級進模、別克轎車安全帶座式多工位級進模、空調(diào)器散熱片多工位級進模,均達到國外同類產(chǎn)品水平。但總體上和國外多工位級進模相比,在制造精度、使用壽命、模具結構和功能上,仍存在一定差距。本文將對電位器接線片沖壓工藝與多工位級進模設計作一個系統(tǒng)、詳細的介紹。畢業(yè)設計的意義就在于綜合運用所學課程的理論和生產(chǎn)實際知識,進行多工位級進模設計工作的實際訓練,培養(yǎng)個人獨立工作能力和創(chuàng)新能力,樹立理論聯(lián)系實際和嚴謹求實的工作作風。鞏固、擴充模具專業(yè)課程所學內(nèi)容,掌握多工位級進模的設計方法和步驟。掌握多工位級進模設計的基本技能,如計算分析、計算機繪圖、查閱設計資料和撰寫設計說明書,熟悉標準和規(guī)范。第二章 零件圖分析和計算2.1 工藝分析1.工件圖采用厚 的黃銅帶制成,尺寸公差,形位公差都有較高的要求,外0.4m形復雜,產(chǎn)量大,用級進模生產(chǎn)最為合理,其他加工方法都不經(jīng)濟。2.主要工序有落料、沖孔、成形和彎曲。3.工件圖如圖 2-1 所示。2圖 2-1 電位器接線片示意圖2.2 工藝計算2.2.1 加工零件的彎曲表 2-1 彎曲 時,變薄系數(shù) 和應變中性層位移系數(shù) 的數(shù)值90Xrt0.1 0.25 0.5 1.0 2.0g 0.82 0.87 0.92 0.96 0.99X0.32 0.35 0.38 0.42 0.445r彎曲半徑(mm) ,t料厚(mm)2.2.2 彎曲件的毛坯長度計算這類( )零件變薄不嚴重且斷面畸變較輕,可以按應變中性層長度等于毛r.t坯長度的原則來計算。毛坯長度等于零件直線長度和彎曲部分應變中性層長度之和,即:3(2i ii=rxt180Ll( )1)當 時,則毛坯的展開長度為:90(22()iLlrxt2)2.2.3 彎曲高度要求當彎曲 角時,為了保證工件的彎曲質(zhì)量,必須滿足彎曲件的直角邊高度為:90(圖 2-2) 。當 h 較小時,直角在模具上支持的長度過小,不容易形成足夠的2hrt彎矩,很難得到形狀準確的零件。若 時,則須預先壓槽,再彎曲;或增加彎2hrt邊高度,彎曲后再切掉。如果所彎直角邊帶有斜角,則在斜邊高度小于 的區(qū)段不2rt可能彎曲到要求的角度,而且此處也容易開裂。因此必須改變零件的形狀,加高直邊尺寸。圖 2-2 彎曲角圖中 ,0.81hr0.t.4,所以, ,則須預先壓槽,再彎曲;+2t第三章 工藝方案與模具形式3.1 零件的基本工序該零件有以下基本工序:落料,沖 的圓孔和導正銷,以及六次彎曲。0.5m43.2 模具方案的設計根據(jù)這些基本工序可擬出三種方案:方案一,采用單工序模;方案二,落料沖孔復合,其余單工序;方案三,采用多工位級進模制造。比較三種方案,方案一和方案二,由于工序較多,且需用手工操作,定位難以達到精度要求,質(zhì)量難以保證。由于該零件屬于定型產(chǎn)品中的零件,且大批量生產(chǎn),采用多工位級進模制造能夠達到精度要求,保證質(zhì)量。故選用方案三。第四章 工序及排樣圖設計4.1 加工工序1. 沖壓材料使用黃銅帶,材料厚 ,采用自動送料器送料。0.4m2.排樣如圖 4-1 所示,共 28 個工位。第一工位:沖導正銷孔。第二工位:空工位。第三工位:空工位。第四工位:沖裁 A 區(qū)外形。第五工位:空工位。第六工位:沖 的圓孔。30.5m第七、八、九工位:空工位。第十工位:沖工件 B 區(qū)外形,并向下彎曲尾部 。1.5m第十一工位:空工位。第十二工位:沖裁工件右側 C 區(qū)外形。第十三、十四工位:空工位。第十五工位:沖裁工件 D 部位向上 和寬 彎曲。0.810.35第十六工位:空工位。第十七工位:尾部向下彎曲。第十八工位:空工位。第十九工位:向上彎曲 u 型槽的第二處彎曲。第二十工位:空工位。第二十一工位:向下彎曲 u 型槽上方處彎曲。第二十二工位:空工位。第二十三工位:向上彎曲 u 型槽的第一處彎曲。5第二十四工位:空工位。第二十五工位:尾部的角度彎曲。第二十六工位:空工位。第二十七工位:落料。第二十八工位:空工位。圖 4-1 排樣圖4.2 排樣設計計算排樣時,在保證工件質(zhì)量的前提下,主要考慮如何提高材料的利用率。材料利用率的計算公式如下:一個進距的材料利用率 的計算見式(410%nAbh1)式中A沖裁件面積(包括內(nèi)形結構廢料) ;n一個進距內(nèi)沖裁件數(shù)目;b條料寬度;h進距。第五章 壓力、壓力中心計算5.1 沖裁力1. 沖裁力由下式計算。6(5F=1.25tL1)式中沖裁力(N) ;0L沖裁件的周長(mm) ;t材料厚度(mm) ;材料抗剪強度(Mpa) 。2.各沖裁區(qū)只是沖裁的長度不同,材料剪切強度極限 ,板料厚度40Mpa,用上式可分別計算出各沖裁線長度和沖裁力,見下表 5-1:t0.4m表 5-1 各沖裁線長度和沖裁力部位 LmFN 部位 LmFN1 個導正釘孔 39.4 1884 C 區(qū)沖裁 4 800孔0.59.4 1884 D 區(qū)沖裁落料 31.4 6280A 區(qū)沖裁 4.5 720B 區(qū)沖裁 16 2560 總計 141285.2 彎曲力1. 六個部位的彎曲均屬于自由彎曲,彎曲力用下式計算:(52b0.6KBtFr+2)式中安全系數(shù) ,圓角半徑 ,屈服極限 ,式中板料寬1.3r.1mt=0.4, b240Mpa度 B 不同,六個部位的寬度分別是 、2 個 、 、 和531.m.1。0.351m由上式可以計算出六個部分的彎曲力,分別為 彎曲總和N405267N5、 、 、 和 。為 。96N5.3 總壓力F1428+901875.4 壓力中心1.模具壓力中心是指沖壓時諸沖壓力合力的作用點位置。為了確保壓力機和模具正常工作,應使沖模的壓力中心與壓力機滑塊的中心相重合。對于帶有模柄的沖壓模,壓力中心應通過模柄的軸心線。否則會使沖模和壓力機塊產(chǎn)生偏心載荷,使滑塊和導軌之間產(chǎn)生過大的磨損,模具導向零件加速磨損,降低模具和壓力機的使用壽命。2.沖模的壓力中心,可按下述原則來確定:(1) 對稱形狀的單個沖裁件,沖模的壓力中心就是沖裁件的幾何中心。(2) 工件形狀相同且分布位置對稱時,沖模的壓力中心與零件的對稱中心重合。(3) 形狀復雜的零件、多凸模的壓力中心可用解析計算法求出沖模的壓力中心。解析法的計算依據(jù)是:各分力對某些坐標軸的力矩之代數(shù)和等于諸力的合力對該坐標軸力矩。求出合力作用點的坐標位置 ,即為所求模具的壓力中心。xy( , )計算公式為:(5iipp1p2pn1p1.niniFxFxx3)(5iipp1p2pn1p1.niniFyFyy4)因沖裁力與沖裁周邊長度成正比,所以式中的各沖裁力 、 、 ,可分p1F2p3nF別用各種沖裁周邊長度 、 、 代替,即:1L23nL(512n11. iiniiLxxxLL 5)8(512n11. iiniiLyLyyL 6)根據(jù)以上公式,可計算出壓力中心位于沖導正銷左邊 。9.8m5.5 沖裁間隙5.5.1 沖裁間隙對沖件質(zhì)量的影響沖裁件的質(zhì)量主要是指斷面質(zhì)量、尺寸精度和形狀誤差。斷面應平直、光滑;圓角??;無裂紋、撕裂、夾層和毛刺等缺陷。零件表面應盡可能平整。尺寸應在圖樣規(guī)定的公差范圍之內(nèi)。影響沖裁件質(zhì)量的因素有:凸、凹模間隙值的大小及其分布的均勻性,模具刃口鋒利狀態(tài)、模具結構與制造精度,材料性能等,其中,間隙值大小與分布的均勻程度是主要因素。沖裁件的尺寸精度是指沖裁件實際尺寸與標稱尺寸的差值(),差值越小,精度越高。這個差值包括兩方面的偏差,一是沖裁件相對凸?;虬寄3叽绲钠睿悄>弑旧淼闹圃炱?。沖裁件相對凸模或凹模尺寸的偏差,主要是由于沖裁過程中,材料受拉伸、擠壓、彎曲等作用引起的變形,在加工結束后工件脫離模具時,會產(chǎn)生彈性恢復而造成的。偏差值可能是正的,也可能是負的。影響這一偏差值的因素主要是凸、凹模的間隙。當間隙較大時,材料所受拉伸作用增大,沖裁完畢后,因材料的彈性恢復,沖裁件尺寸向?qū)嶓w方向收縮,使落料件尺寸小于凹摸尺寸,而沖孔件的孔徑則大于凸摸尺寸。當間隙較小時,凸摸壓入扳料接近于擠壓狀態(tài),材料受凸、凹模擠壓力大,壓縮變形大,沖裁完畢后,材料的彈性恢復使落料件尺寸增大,而沖孔件的孔徑則變小。此外,尺寸變化量的大小還與材料力學性能、厚度、軋制方向、沖裁件形狀等因素有關。材料軟,彈性變形量較小,沖裁后彈性恢復量就小,零件的精度也就高。材料硬,彈件恢復量就大。以上是在模具制造精度一定的前提下進行的,間隙對沖裁件精度的影響比模具本身制造精度的影響要小得多,若模具刃口制造精度低,沖裁出的工件精度也就無法得到保證。模具的磨損及模具刃口在壓力作用下產(chǎn)生的彈性變形也會影響到間隙及沖裁件應力狀態(tài)的改變,對沖裁件的質(zhì)量會產(chǎn)生綜合性影響。95.5.2 對模具壽命的影響沖裁模具的壽命以沖出合格制品的沖裁次數(shù)來衡量,分兩次刃磨間的壽命與全部磨損后總的壽命。沖裁過程中,模具的損壞有磨損、崩刃、折斷、啃壞等多種形式。影響模具壽命的因素很多,有模具間隙;模具制造材料和精度、表面粗糙度;被加工材料特性;沖裁件輪廓形狀和潤滑條件等。模具間隙是其中的一個主要因素。因為沖裁過程中,模具端面受到很大的垂直壓力與側壓力,而模具表面與材料的接觸面僅局限在刃口附近的狹小區(qū)域,這就意味著即使整個模具在許用壓應力下工作,但在模具刃口處所受的壓力也非常大。這種高的壓力會使沖裁模具和板材的接觸面之間產(chǎn)生局部附著現(xiàn)象,當接觸面發(fā)生相對滑動時,附著部分便發(fā)生剪切而引起磨損附著磨損。其磨損量與接觸壓力、相對滑動距離成正比,與材料屈服強度成反比。它被認為是模具磨損的主要形式。當模具間隙減小時,接觸壓力(垂直力、側壓力、摩擦力)會隨之增大,摩擦距離隨之增長,摩擦發(fā)熱嚴重,因此模具磨損加劇。而接觸壓力的增大,還會引起刃口的壓縮疲勞破壞,使之崩刃。小間隙還會產(chǎn)生凹模脹裂,小凸模折斷,凸、凹模相互啃刃等異常損壞。這些都導致模具壽命大大降低。因此,適當增大模具間隙,可使凸、凹模側面與材料間摩擦減小,并減緩間隙不均勻的不利因素,從而提高模具壽命。但間隙過大時。板料的彎曲拉伸相應增大,使模具刃口端面上的正壓力增大,容易產(chǎn)生崩刃或產(chǎn)生塑性變形使磨損加劇,降低模具壽命。同時,間隙過大,卸料力會隨之增大,也會增加模具的磨損。所以間隙是影響模具壽命的個重要因素。圖 5-1 間隙與磨損的關系從圖 5-1 可看出,凹模端面的磨損比凸模大,這是由于凹模端面上材料的滑動比較自由,而凸模下面的材料沿板面方向的移動受到限制的原因,而圖中所看到的凸模側面的磨損最大,是因為從凸模上卸料,長距離摩擦加劇了側面的磨損,若采用較大間隙可使孔徑在沖裁后因回彈增大卸料時減少與凸模的摩擦,從而減少凸模側面的10磨損。模具刃口磨損,帶來刃口的鈍化和間隙的增加,使制件尺寸精度降低,沖裁能量增大,斷面粗糙。刃口的鈍化會使裂紋發(fā)生點由刃口端面向側面移動,發(fā)生在刃口磨損部分終點處,從而產(chǎn)生大小和磨損量相當?shù)拿?凸模刃口磨鈍,毛刺產(chǎn)生在落料件上,凹模刀口磨鈍,毛刺產(chǎn)生在孔上),所以必須注意盡量減少模具的磨損。為提高模具壽命, 一般需采用較大間隙,若制件精度要求不高時。采用合理大間隙,使 2/t 達到15一 25,模具壽命可提高 35 倍,若采用小間隙,就必須提高模具硬度與模具制造精度,在沖裁刃口進行充分的潤滑,以減少磨損。5.5.3 對沖裁力及卸料力的影響當間隙減小時,凸模壓入板材的情況接近于擠壓狀態(tài),材料所受拉應力減小,壓應力增大,板料不易產(chǎn)生裂紋,因此最大沖裁力增大。當間隙增大時,材料所受拉應力增大,材料容易產(chǎn)生裂紋,因此沖裁力減小。繼續(xù)增大間隙值,凸、凹模刃口產(chǎn)生的裂紋不相重合,會發(fā)生二次斷裂沖裁力下降變緩。當間隙增大時,沖裁件光亮帶窄,落料件尺寸偏差為負,沖孔件尺寸偏差為正,因而使卸料力、推件力或頂件力減小。間隙繼續(xù)增大時,制件毛刺增大,卸料力、頂件力迅速增大。5.5.4 合理間隙選用凸、凹模間隙是沖裁過程最重要的工藝參數(shù),它對沖裁件質(zhì)量、模具壽命、沖裁力和卸料力等都有很大的影響,因此,設計模具時,一定要選擇一個合理的間隙,使沖裁件的斷面質(zhì)量好,尺寸精度高,模具壽命長,所需沖裁力小,但嚴格說來,并不存在一個同時滿足所有理想要求的合理間隙??紤]到模具制造中的偏差及使用中的磨損,生產(chǎn)中通常是選擇一個適當?shù)姆秶鳛楹侠黹g隙,只要模具間隙在這個范圍內(nèi),就可以基本滿足以上各項要求,沖出合格制件。這個范圍的最小值稱為最小合理間隙,最大值稱為最大合理間隙 ??紤]到模具在使用過程中的逐步磨損,設minZmaxZ計和制造新模具時應采用最小合理間隙。理論計算法,確定間隙時理論計算的依據(jù)主要是:在合理間隙情況下沖裁時,材料在凸、凹模刃口處產(chǎn)生的裂紋成直線會合。從圖 5.53 所示的幾何關系可得出計算合理間隙的公式(5002()2(1)hZthgttg7)式中 -產(chǎn)生裂紋時的凸模壓入探度 (mm)0h11t料厚(mm);最大切應力方向與垂線間夾角(即裂紋方向角)。由上式可知,間隙 z 與板材厚度、相對壓入深度 /t、裂紋方向角 有關。而0h、 又與材料性質(zhì)有關,但是這種方法不方便。0h5.6 模具刃口尺寸計算沖裁件的尺寸精度主要取決于凹、凸模刃口尺寸及公差、模具的合理間隙值也是靠凸、凹模刃口尺寸及其公差來保證的,因此,正確的確定凸、凹模刃口尺寸及其公差,是沖裁設計中的一項重要工作。5.6.1 凸、凹模刃口尺寸計算原則(1)落料時,先確定凹模刃口尺寸,凹模刃口的基本尺寸取接近或等于制件的最小極限尺寸,以保證凹模磨損在一定范圍內(nèi),仍能沖出合格制件。凸模刃口的基本尺寸按凹模的刃口基本尺寸減小一個最小合理間隙來確定。(2)沖孔時,先確定凸模刃口尺寸。凸模刃口尺寸的基本尺寸接近或等于孔的最大極限尺寸,以保證凸模磨損在一定范圍內(nèi),仍能沖出合格制件。凹模刃口的基本尺寸按凸模的刃口基本尺寸減小一個最小合理間隙來確定。(3)凸模和凹模刃口的制造公差,主要取決于沖裁件的精度和形狀,一般模具的制造精度比沖裁件的精度至少高 1-2 級,若制件沒有標注公差,則對于非圓形件按國家非配合尺寸的 IT14 級精度來處理,圓形件一般可按 IT10 級精度來處理,本次計算采用GB/T1804-2000 計算表 5-2 因數(shù) x非圓形 值x圓形 值x1 0.75 0.5 0.75 0.5材料厚度t/mm 制造公差 /mmA1 0.160.17-0.35 0.360.16 0.161-2 0.20 0.21-0.41 0.42 0.20 0.202-4 0.24 0.25-0.49 0.50 0.24 0.244 0.30 0.21-0.59 0.60 0.30 0.30125.6.2 凸、凹模尺寸計算1、沖孔沖孔部分由于結構簡單,故采用凸凹模分別加工法。查手冊可知落料、沖孔模刃口間隙取 ,取因數(shù)minmax0.1 Z0.13Z,=0.5,制造等級采用 m(中等級) 。x孔徑為 7: 000in .2.2()(6.854)7ppd.mi00071ddZ孔徑為 8: in()pp.2.2(.854)8min0ddpZ0.0.1校核 ,有(0.020+0.020) (0.13-0.10),故 、 不滿足要axip pd求,則凸凹模制造公差應重新確定:mmmaxin0.4()0.43.012pZmmai.6.6.8d即,孔 7: , ;0.12p0.187d孔 8: , 0.d.0注: 、 分別為沖孔凹模和凸模的刃口尺寸(mm) ;a、 分別為凹模和凸模的制造公差(mm) ;dp凸模最小尺寸(mm)min最小合理間隙(mm)iZ 系數(shù);x 公件的公差(mm) ;13第六章 級進模具設計6.1 模具總結構設計1由于材料厚度為 ,所以各雙面沖裁間隙只有 ,因而要求模0.4m0.35m架有很高的導向精度,故選用滾珠導向鋼板模架。模具結構如裝配圖所示。模具上模部分由上模座、墊板、凸模固定板、彈壓卸料板及各個凸模組成。卸料板分為獨立的三塊,每塊卸料板均安裝兩個小導柱導向,每塊卸料板又由卸料板基體和卸料板鑲塊組成。模具下模部分由下模座、墊板、凹模板、凹模鑲塊、導料板、彈頂器組成。模具還裝有限位柱和安全檢測裝置。2.模具零件的加工精度和配合要求表 6-1 模具零件的加工精度及其相互配合配合零件名稱 精度及配合導柱與下模座 H7/r6導套與上模座 H7/r6導柱與導套 H7/h6模柄(壓入式)與上模座 H7/m6續(xù)表 6-1凸模與凸模固定板 H7/m6圓柱銷與凸模固定板、上下模座等 H7/n6固定擋料銷與卸料板 H7/m6凸凹模與凸凹模固定板 H7/n6螺釘與螺桿孔 0.5 或 1mm(單邊)卸料板與凸凹模 0.10.5mm(單邊)推件塊與凹模 0.10.5mm(單邊)推桿與模柄 0.51mm(單邊)146.2 凸模的結構設計模具共有各種用途的凸模 13 個,且多為細小的凸模。凸模的保護主要依靠卸料板和鑲在卸料板上的凸模保護套來實現(xiàn)。凸模的固定方法為:對于圓凸模均設計為臺階式,用凸模固定板固定;對于非圓凸模,上部設計為矩形,與凸模固定板上的矩形孔配合,靠近凸模最上部鉆孔或開槽,用銷釘或卡塊固定在凸模固定板內(nèi)。6.3 凹模的結構設計由于該工件比較復雜,所以將凹模設計為鑲拼結構,并用內(nèi)六角螺釘和銷釘將其固定在上模座上。凹模采用鑲拼結構后,雖然拼塊的裝配和模具結構變得復雜,但是分塊后凹模易于加工,精度容易保證,而且還可以將懸臂結構單獨作為一個部分,損壞后易于更換,可避免整體凹模報廢。凸模和凹模鑲拼結構設計的依據(jù)是凸、凹模形狀、尺寸及其受力情況、沖裁板料厚度等。鑲拼結構設計的一般原則如下:1.力求改善加工工藝性,減少鉗工工作量,提高模具加工精度 (1)盡量將形狀復雜的內(nèi)形加工變成外形加工,以便于切削加工和磨削。(2)盡量使分割后拼塊的形狀、尺寸相同,可以幾塊同時加工和磨削,一般沿對稱線分割可以實現(xiàn)這個目的。(3)應沿轉角、尖角分割,并盡量使拼塊角度大于或等于 90。(4)圓弧盡量單獨分塊,拼接線應在離切點 47mm 的直線處,大圓弧和長直線可以分為幾塊。(5)拼接線應與刃口垂直,而且不宜過長,一般為 1215mm。 2.便于裝配調(diào)整和維修 (1)比較薄弱或容易磨損的局部凸出或凹進部分,應單獨分為一塊。(2)拼塊之間應能通過磨削或增減墊片方法,調(diào)整其間隙或保證中心距公差。(3)拼塊之間應盡量以凸、凹槽形相嵌,便于拼塊定位,防止在沖壓過程發(fā)生相對移動。滿足沖壓工藝要求,提高沖壓件質(zhì)量 為此,凸模與凹模的拼接線應至少錯開35mm,以免沖裁件產(chǎn)生毛刺;拉深模拼接線應避開材料有增厚部位,以免零件表面出現(xiàn)拉痕。凹模輪廓尺寸包括凹模板的平面尺寸 及厚度尺寸 H。從凹模刃口至()LB長 寬凹15模外緣的最短距離稱為凹模的壁厚 c,對于形狀復雜凹模,為了使壓力中心與凹模板中心重合,凹模平面尺寸應按下式計算:(61)2Ll(62)Bbc沿凹模長度方向壓力中心至最遠刃口間距的 2 倍(mm) ;l沿凹模寬度方向刃口孔型的最大距離(mm) ;b凹模壁厚(mm) ,主要考慮布置螺孔與銷孔的需要,同時也要保證凹模的強度和c剛度,查手冊可知壁厚在 42-52 之間,取 52mm。凹模的厚度主要是從螺釘旋入深度和凹模剛度的需要兩方面考慮,一般應不小于8mm,隨著凹模板平面尺寸的增大,其厚度也相應地增大。凹模板的厚度可按如下經(jīng)驗公式估算:(63)3120.HKF= .641803=7m式中 沖裁力(N);F凹模材料修正系數(shù),合金工具鋼取 ,碳素工具鋼取 ;1K1K1.3K凹模刃口周邊長度修正系數(shù),如表 632綜合上述計算結果取凹模尺寸為 。34207m表 6-2 修正系數(shù) 2刃口長度(mm) 修正系數(shù) 2K刃口長度(mm) 修正系數(shù) 2K500 1.66.4 導料系統(tǒng)在凹模上裝有導尺、導尺內(nèi)側開槽,以防止條料向上躍出導尺。在導尺的條料進口處裝有彈性側壓裝置,其結構如圖 6-1 所示,側壓裝置的作用n編號: 畢業(yè)設計(論文)外文翻譯(原文)院 (系): 機電工程學院 專 業(yè):機械設計制造及其自動化 學生姓名:學 號:指導教師單位:姓 名:職 稱:1The development trend of the numerical control technology1. NUMERICAL CONTROLNumerical control(NC)is a form of programmable automation in which the processing equipment is controlled by means of numbers,letters,and other symbolsThe numbers,letters,and symbols are coded in an appropriate format to define a program of instructions for a particular workpart or jobWhen the job changes,the program of instructions is changedThe capability to change the program is what makes NC suitable for low-and medium-volume productionIt is much easier to write programs than to make major alterations of the processing equipmentThere are two basic types of numerically controlled machine tools:pointtopoint and continuouspath(also called contouring)Pointtopoint machines use unsynchronized motors,with the result that the position of the machining head Can be assured only upon completion of a movement,or while only one motor is runningMachines of this type are principally used for straightline cuts or for drilling or boring The NC system consists of the following components:data input,the tape reader with the control unit,feedback devices,and the metalcutting machine tool or other type of NC equipmentData input,also called“mantocontrol link”,may be provided to the machine tool manually,or entirely by automatic meansManual methods when used as the sole source of input data are restricted to a relatively small number of inputsExamples of manually operated devices are keyboard dials,pushbuttons,switches,or thumbwheel selectorsThese are located on a console near the machineDials ale analog devices usually connected to a syn-chro-type resolver or potentiometerIn most cases,pushbuttons,switches,and other similar types of selectors aye digital input devicesManual input requires that the operator set the 2controls for each operationIt is a slow and tedious process and is seldom justified except in elementary machining applications or in special casesIn practically all cases,information is automatically supplied to the control unit and the machine tool by cards,punched tapes,or by magnetic tapeEightchannel punched paper tape is the most commonly used form of data input for conventional NC systemsThe coded instructions on the tape consist of sections of punched holes called blocksEach block represents a machine function,a machining operation,or a combination of the twoThe entire NC program on a tape is made up of an accumulation of these successive data blocksPrograms resulting in long tapes all wound on reels like motion-picture filmPrograms on relatively short tapes may be continuously repeated by joining the two ends of the tape to form a loopOnce installed,the tape is used again and again without further handlingIn this case,the operator simply loads and unloads the partsPunched tapes ale prepared on type writers with special tapepunching attachments or in tape punching units connected directly to acomputer systemTape production is rarely error-freeErrors may be initially caused by the part programmer,in card punching or compilation,or as a result of physical damage to the tape during handling,etcSeveral trial runs are often necessary to remove all errors and produce an acceptable working tape While the data on the tape is fed automatically,the actual programming steps ale done manuallyBefore the coded tape may be prepared,the programmer,often working with a planner or a process engineer, must select the appropriate NC machine tool,determine the kind of material to be machined,calculate the speeds and feeds,and decide upon the type of tooling needed. The dimensions on the part print are closely examined to determine a suitable zero reference point from which to start the programA program manuscript is then written which gives coded numerical instructions describing the sequence of operations that the machine tool is required to follow to cut the part to the drawing specifications3The control unit receives and stores all coded data until a complete block of information has been accumulatedIt then interprets the coded instruction and directs the machine tool through the required motionsThe function of the control unit may be better understood by comparing it to the action of a dial telephone,where,as each digit is dialed,it is storedWhen the entire number has been dialed,the equipment becomes activated and the call is completedSilicon photo diodes,located in the tape reader head on the control unit,detect light as it passes through the holes in the moving tapeThe light beams are converted to electrical energy,which is amplified to further strengthen the signalThe signals are then sent to registers in the control unit, where actuation signals are relayed to the machine tool drivesSome photoelectric devices are capable of reading at rates up to 1000 characters per secondHigh reading rates are necessary to maintain continuous machinetool motion;otherwise dwell marks may be generated by the cutter on the part during contouring operationsThe reading device must be capable of reading data blocks at a rate faster than the control system can process the dataA feedback device is a safeguard used on some NC installations to constantly compensate for errors between the commanded position and the actual location of the moving slides of the machine toolAn NC machine equipped with this kind of a direct feedback checking device has what is known as a closed-loop systemPositioning control is accomplished by a sensor which,during the actual operation,records the position of the slides and relays this information back to the control unitSignals thus received ale compared to input signals on the tape,and any discrepancy between them is automatically rectifiedIn an alternative system,called an openloop system,the machine is positioned solely by stepping motor dri4ves in response to commands by a controllersThere are three basic types of NC motions, as follows: Point-to-point or Positional Control In point-to-point control the machine tool elements (tools, table, etc.) are moved to programmed locations and the machining operations performed after the motions are completed. The path or speed of movement between locations is unimportant; only the coordinates of the end points of the motions are accurately controlled. This type of control is suitable for drill presses and some boring machines, where drilling, tapping, or boring operations must be performed at various locations on the work piece. Straight-Line or Linear Control Straight-Line control systems are able to move the cutting tool parallel to one of the major axes of the machine tool at a controlled rate suitable for machining. It is normally only possible to move in one direction at a time, so angular cuts on the work piece are not possible, consequently, for milling machines, only rectangular configurations can be machined or for lathes only surfaces parallel or perpendicular to the spindle axis can be machined. This type of controlled motion is often referred to as linear control or a half-axis of control. Machines with this form of control are also capable of point-to-point control.Continuous Path or Contouring Control In continuous path control the motions of two or more of the machine axes are controlled simultaneously, so that the position and velocity of the can be tool are changed continuously. In this way curves and surfaces can be machined at a controlled feed rate. It is the function of the interpolator in the controller to determine the increments of the individual controlled axes of the machines necessary to produce the desired motion. This type of control is referred to as continuous control or a full axis of control.Some terminology concerning controlled motions for NC machines has been introduced. For example, some machines are referred to as four-or five-or even six-axis machines. For a vertical milling machine three axes of control are fairly obvious, these being the usual X, Y, Z coordinate directions. A fourth or fifth axis of control would imply some form of rotary table to index the work piece or possibly to provide angular motion 5of the work head. Thus, in NC terminology an axis of control is any controlled motion of the machine elements (spindles, tables, etc). A further complication is use of the term half-axis of control; for example, many milling machines are referred to as 2.5-axis machine. This means that continuous control is possible for two motions (axes) and only linear control is possible for the third axis. Applied to vertical milling machines, 2.5axis control means contouring in the X, Y plane and linear motion only in the Z direction. With these machines three-dimensional objects have to be machined with water lines around the surface at different heights. With an alternative terminology the same machine could be called a 2CL machine (C for continuous, L for linear control). Thus, a milling machine with continuous control in the X, Y, Z directions could be termed be a three-axis machine or a 3c machine, Similarly, lathes are usually two axis or 2C machines. The degree of work precision depends almost entirely upon the accuracy of the lead screw and the rigidity of the machine structureWith this systemthere is no self-correcting action or feedback of information to the control unitIn the event of an unexpected malfunction,the control unit continues to put out pulses of electrical currentIf,for example,the table on a NC milling machine were suddenly to become overloaded,no response would be sent back to the controllerBecause stepping motors are not sensitive to load variations,many NC systems are designed to permit the motors to stall when the resisting torque exceeds the motor torqueOther systems are in use,however,which in spite of the possibility of damage to the machine structure or to the mechanical system,ale designed with special hightorque stepping motorsIn this case,the motors have sufficient capacity to“overpowerthe system in the event of almost any contingency The original NC used the closedloop systemOf the two systems,closed and open loop,closed loop is more accurate and,as a consequence,is generally more expensiveInitially,openloop systems were used almost entirely for light-duty applications because of inherent power limitations previously associated with conventional electric stepping motorsRecent advances in the development of electro hydraulic stepping motors have led to increasingly heavier machine load applications62.NC technology development trends2.1 NC system developments at home and abroad With the rapid development of computer technology, the traditional beginning of a fundamental change manufacturing, the industrial developed countries spent huge sums of money on the modern manufacturing technology research and development, to create a new model. In modern manufacturing systems, CNC technology is the key to technology, which combines microelectronics, computers, information processing, automatic detection, automatic control, such as the integration of advanced, a high-precision, high-efficiency, flexible automation, and other characteristics, the manufacturing industry Flexible automation, integrated, intelligent play the pivotal role. At present, NC technology is undergoing a fundamental change, from a special closed-loop control mode to general-purpose real-time dynamic open all closed-loop control mode. In the integrated on the basis of the CNC systems ultra-thin, ultra-light; on the basis of the intelligent, integrated computers, multimedia, fuzzy control, neural network and other technical disciplines, NC system to achieve high-speed, high-precision, Efficient control, automatic processing can be amended to regulate compensation and the parameters for an online intelligent fault diagnosis and treatment of the network based on the CAD / CAM and CNC systems integration as one machine network, makes the central government centralized control of the group control processing. The application of the technology of numerical control has not only brought the revolutionary change to traditional manufacturing industry, make the manufacturing industry become the industrialized symbol , and with the constant development of the technology of numerical control and enlargement of application, the development of he some important trades (IT , car , light industry , medical treatment ,etc. ) to the national economy and the peoples livelihood plays a more and more important role, because these trade necessary digitization that equipped has already been the main trend of modern development.For a long time, Chinas CNC system for traditional closed architecture, but only as a non-intelligent CNC machine controller. Process 7variables based on experience in the form of pre-fixed parameters, processing procedures before the actual processing by hand or through CAD / CAM and automatic programming system prepared. CAD / CAM and CNC have no feedback control link, the entire manufacturing process CNC is a closed ring-opening implementing agencies. In a complex and changing environment under the conditions of processing tool in the process of composition, workpiece material, spindle speed, feed rate, tool path, cutting depth, step, allowance and other processing parameters, not at the scene circumstances under external interference and real-time dynamic random factors, not by random amendment feedback control link CAD / CAM settings volume, in turn, affect the work of CNC machining efficiency and product quality. Clearly, the traditional fixed CNC system that controlled mode and closed architecture, limiting the CNC to the development of more intelligent control variables, can no longer meet the increasingly complex manufacturing process, therefore, the CNC technology in the potential for change inevitable. The technology of numerical control of our country started in 1958, the development course in the past 50 years can roughly be divided into 3 stages: The first stage is from 1958 to 1979, i.e. closed developing stage. In this stages, technology of foreign countries blockade and basic restriction of terms of our country, the development of the technology of numerical control is comparatively slow. During Sixth Five-Year Plan Period , the Seventh Five-Year Plan Period of the country in second stage and earlier stage in the Eighth Five-Year Plan Period , introduce technology , digest and assimilate, the stage of establishing the system of production domesticization arisesing tentatively. At this stage , because of reform and opening-up and national attention , and study the improvement of the development environment and international environment, research , development and all making considerable progress in production domesticization of the products of the technology of numerical control of our country. The third stage is that on the later stage in the Eighth Five-Year Plan Period of the country and during the Ninth Five-Year Plan Period , implement the research of industrialization , enter market competition stage. At this stage, made substantive progress in 8industrialization of the domestic numerical control equipment of our country. In the Ninth Five-Year Plan latter stage, domestic numerical control domestic market share of lathe reach 50% , mix domestic numerical control system (popular ) to up to 10%. Review the development course in the past 50 years of technology of numerical control of our country, especially pass the brainstorm of 4 Five-Year Plans, all in all has made following achievements.a. Have establish the foundation of the technical development of numerical control, has basically mastered the technology of modern numerical control. Our country know from numerical control system , servo urge , numerical control host computer , special plane and their basic of fittings basically already now, among them most technology have already possessed the foundation that is commercialized and developed , some technology has already, industrialization commercialized.a.Have formed the industrial base of numerical control tentatively. In tackling key problems the foundation that the achievement and some technology commercialize , set up the systematic factories of numerical control with production capacity of batch such as numerical control of Central China , spaceflight numerical control etc. Electrical machinery plant of Lanzhou, a batch of servo systems and first machine tool plant , first machine tool plant of Jinan of servo electrical machinery factory and Beijing ,etc. several numerical control host computer factories such as the numerical control in Central China. These factories have basically formed the numerical control industrial base of our country.b.Have set up research of a numerical control, development , managerial talents basic team . Though has made considerable progress in research and development and industrialization of the technology of numerical control, but we will realize soberly, the research and development of the technology of advanced numerical control of our country, there is greater disparity between current situation and current demand of our country of engineering level especially in industrialization. Though very fast from longitudinal development to watch our country, horizontal until (contrast 9with foreign countries ) , the engineering level has disparity, there is disparity too in development speed in some aspects, i.e. the disparity of engineering level between some high-grade , precision and advanced numerical control equipment has the tendency to expand . Watch from world , estimate roughly as follows about the numerical control engineering level of our country and industrialization level.2.2 Strategic consideration and Development tacticsOur country of strategic consideration makes the big country , should try hard to accept the front instead of the back transformation in the world industry shifts , should master and make key technology advancedly , otherwise in a new round of international industrial structure adjustment, of our country manufacturing industry step forward the empty core . We regard resource , environment , market as cost, possibility got to exchange assemble the centre , but not master the status of the manufacturing center of key technology , will so influence the development process of the modern manufacturing industry of our country seriously.We should stand in the height of national security strategy paying attention to the technology of numerical control and industrys question , at first seen from social safety, because manufacturing industry whether our country obtain employment most populous trade, the development of manufacturing industry not only can improve the peoples living standard but also can relieve the pressure of employment ofour country , ensure the stability of the society; Secondly seen from security of national defence, the western developed country has classified all the high-grade , precision and advanced numerical control products as the strategic materials of the country, realize embargo and restriction to our country, Toshiba incident and Cox Report is the best illustration. Proceed from the angles of the fundamental realities of the country of our country, regard the strategic demand of the country and market demand of the national economy as the direction, regard improving our country and making the comprehensive competitive power of equipping industry and 10industrialization level as the goal, use the systematic method , be able to choose the support technology that the initial our country makes the key technology upgraded in development of equipping industry and supports the development
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